FN Archimer Export Format
PT J
TI An Annual Cycle of Submesoscale Vertical Flow and Restratification in the Upper Ocean
BT 
AF Yu, Xiaolong
   Naveira Garabato, Alberto C.
   Martin, Adrian P
   Buckingham, Christian
   Brannigan, Liam
   Su, Zhan
AS 1:1;2:1;3:2;4:3;5:4;6:5;
FF 1:;2:;3:;4:;5:;6:;
C1 Department of Ocean and Earth Sciences, University of Southampton, UK
   National Oceanography Centre, Southampton, UK
   Univ. Brest, CNRS, IRD, Ifremer, Laboratoire d’Océanographie Physique et Spatiale (LOPS), IUEM, Brest, France
   Department of Meteorology, Stockholm University, Stockholm, Sweden
   Environmental Science and Engineering, California Institute of Technology, USA
C2 UNIV SOUTHAMPTON, UK
   NOC, UK
   UBO, FRANCE
   UNIV STOCKHOLM, SWEDEN
   CALTECH, USA
UM LOPS
IN WOS Cotutelle UMR
   copubli-europe
   copubli-int-hors-europe
IF 3.318
TC 92
UR https://archimer.ifremer.fr/doc/00489/60076/63398.pdf
LA English
DT Article
DE ;Ocean;Atlantic Ocean;Ageostrophic circulations;Frontogenesis;frontolysis;In situ oceanic observations
AB Numerical simulations suggest that submesoscale turbulence may transform lateral buoyancy gradients into vertical stratification, and thus restratify the upper ocean via vertical flow. However, the observational evidence for this restratifying process has been lacking due to the difficulty in measuring such ephemeral phenomena, particularly over periods of months to years. This study presents an annual cycle of the vertical velocity and associated restratification estimated from two nested clusters of meso- and submesoscale-resolving moorings, deployed in a typical mid-ocean area of the Northeast Atlantic. Vertical velocities inferred using the non-diffusive density equation are substantially stronger at submesoscales (horizontal scales of 1-10 km) than at mesoscales (horizontal scales of 10-100 km), with respective root mean square values of 38.0 ± 6.9 m/day and 22.5 ± 3.3 m/day. The largest submesoscale vertical velocities and rates of restratification occur in events of a few days’ duration in winter and spring, and extend down to at least 200 m below the mixed layer base. These events commonly coincide with the enhancement of submesoscale lateral buoyancy gradients, which is itself associated with persistent mesoscale frontogenesis. This suggests that mesoscale frontogenesis is a regular precursor of the submesoscale turbulence that restratifies the upper ocean. The upper-ocean restratification induced by submesoscale motions integrated over the annual cycle is comparable in magnitude to the net destratification driven by local atmospheric cooling, indicating that submesoscale flows play a significant role in determining the climatological upper-ocean stratification in the study area. 
PY 2019
PD JUL
SO Journal Of Physical Oceanography
SN 0022-3670
PU American Meteorological Society
VL 49
IS 6
UT 000469236600003
BP 1439
EP 1461
DI 10.1175/JPO-D-18-0253.1
ID 60076
ER

EF